The Mother Who Seeks After God - Daily Devotions for Busy Mums, Laura Martin, £7.99 Short easy to read chapters with musings and meditations on a mother's life. Includes relevant scripture references. Deserves reflective reading.
This well known book is now available as a double DVD set (£25) and a study guide (£3.75).
Highly thought of, Ruth Bryan's letters have been likened to Samuel Rutherford's. Devotional in nature, they are rich in mature spiritual guidance.
If these don't give you any ideas, just give me a call and describe your Mother - I bet I could come up with something perfectly suited (ask for Lorna when you ring - Jeremy probably doesn't even know when Mother's Day is!)